The present invention relates to material removing tools, particularly to tools which can be used with advantage to remove material from metallic workpieces. Still more particularly, the invention relates to improvements in material removing tools of the type wherein a metallic support is connected with a cutter having several cutting edges.
German Pat. No. 1 800 195 discloses a material removing tool wherein the support is made of steel and the cutter consists of a harder metallic material. The cutter has four cutting edges and the tool is designed to be mounted in a number of different positions in each of which a different cutting edge can remove material from workpieces. A drawback of the patented tool is that, if the cutter develops a crack, the entire tool must be discarded even though one or more cutting edges are still capable of removing material from workpieces.
British Pat. No. 1,493,028 discloses a modified material removing tool wherein a support of hard and tough steel carries several strip-shaped cutters made of hard metal or a ceramic material. The cutter is disposed at one side of the support and exhibits only two cutting edges. A drawback of this tool is that it must be discarded after a relatively short period of use due to the fact that it comprises only two cutting edges. Furthermore, the application of strips to the material of the support presents serious problems. As a rule, the application involves soldering of the harder material to the support.
German patent application No. P 34 33 184.0-14 discloses a further material removing tool wherein a plate-like support has a substantially Z-shaped cutout for a substantially Z-shaped insert of hard material which is capable of removing metal from workpieces. The insert extends beyond both sides of the support so that it provides two pairs of cutting edges. A drawback of such material removing tools is their high cost.